Three-dimensional (3-D) printing is an additive manufacturing process that allows for the manufacture of objects by “building up” an object. In contrast to subtractive techniques, such as machining, in which material is removed from a bulk material in order to form the shape of an object, 3-D printing lays down successive layers of material to form the shape of an object. Typical materials used for 3-D printing may include plastics, ceramics, and metals.